Which one is the correct answer, and why?
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Answer:
D f(n) = 7n-12
Step-by-step explanation:
The first term is -5
The second term is -5+7 =2
The common difference is 7
an = a1 +d(n-1) where d is the common difference
= -5 +7(n-1)
Distribute the 7
= -5 +7n -7
7n -12